Actual Side Effects From Virtual Reality

`Cybersickness,' Other Maladies

August 14, 1995|By Jon Van, Tribune Staff Writer.

The young student volunteer had been wearing a virtual-reality headset for a few hours, exploring an experimental program intended to help surgeons plan operations more efficiently, and the experience left her warm and weary.

After taking off the equipment to feel a real breeze, she reached for a cold can of soda to quench her thirst, raising the can toward her face.

But as she tried to sip the soda, the woman found she was pouring it into her eye instead of her mouth, because an embarrassing perceptual distortion lingered from her extended trip into virtual reality.

Such disorientation in a surgeon won't instill patient confidence, but provides instead a graphic illustration of a problem inherent in virtual-reality technology that some are calling cybersickness.

Disorientation, queasiness, nausea and headaches are among symptoms some experience after using virtual-reality equipment for extended periods. And researchers say that a few people may even have disorienting flashbacks hours or days after their virtual-reality encounter.

As electronics companies gear up to peddle virtual-reality games by the millions, and the technology is touted as the newest means of saving money and boosting efficiency in product design, manufacturing and medicine, the tendency for some people to get sick and disoriented is a nagging problem that will not go away.

Some advocates of virtual reality want the industry to study the phenomenon and set industry standards to avoid widespread outbreaks of cybersickness that could spawn lawsuits and give the technology a black eye.

"I think we'll arrive at a point of some formal certification of VR head-mounted displays," said Chris Yewdall, general manager for Virtuality Entertainment Inc., Irving, Texas., the U.S. division of Virtuality Group PLC, the British giant that dominates the virtual-reality equipment business.

He added: "It's needed to protect the customer and to protect the industry. Because if someone doesn't design a visor diligently, the consequences for the industry as a whole could be quite damaging."

With more than 200 companies and many innovators in the virtual-reality field, the industry needs something like a virtual-reality Underwriters Laboratories to put its seal of approval on products, he said.

But even the best designed virtual-reality equipment is no guarantee against cybersickness. In fact, there still isn't much known about what causes motion sickness or flight-simulator disorientation, which are two cousins to cybersickness.

Despite decades of study, it still isn't possible to determine who will or won't get sick when they fly into the weightlessness of space.

Flashbacks, another symptom of cybersickness, are uncommon, but they do occur among some pilots who use flight simulators, said Robert S. Kennedy, a psychologist with Essex Corp., an Orlando company that specializes in human-machine interactions.

Still, scientists do understand what causes some cybersickness. The disorientation of the woman who poured soda into her eye was a direct result of the design of the equipment she was wearing, said Frank Biocca, a communications researcher at the University of North Carolina in Chapel Hill.

To superimpose X-ray images over a person's real-world view, the headset was made so the wearer gazed directly into two video images placed directly in front of her eyes. The real-world view came from miniature video cameras mounted atop the headset that fed images to the tiny screens.

The intent was to give doctors a real-life version of Superman's X-ray vision.

"This design meant that the user's vantage point was a few inches above her actual eyes," said Biocca. "When your brain discovers that your eye position has changed relative to the rest of the body, it adapts. This is a natural thing that happens as children grow taller.

"In this case, after someone wore the headset for a while, her brain would adjust to the new virtual eye position, and when she took off the headset, the brain retained that adjustment. So when her hand raised a soda to where her body thought her mouth should be, it was a few inches too high.

"This design was particularly disruptive because it was meant to help surgeons," he added. "Disrupting a surgeon's hand-eye coordination could be dangerous."

Researchers have studied extensively the effects on a person's brain when the visual information he receives contradicts information coming from the inner ear and other parts of the body, something they call vestibular adaptation.

In the 1960s, scientists were surprised at how quickly people could adjust when they wore prism glasses that reversed their world view or turned it upside down, said Dr. Timothy Hain, an associate professor of neurology at Northwestern University.